Isonicotinic acid

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-10-17 to 2016-12-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Isonicotinic acid

EC Number:

200-228-2

EC Name:

Isonicotinic acid

Cas Number:

55-22-1

Molecular formula:

C6H5NO2

IUPAC Name:

isonicotinic acid

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study reports): JNJ-40064973-AAA (Isonicotinezuur)
- Physical state: solid (powder)
- Appearance: white powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: M15HB3488
- manufacture date: 2015-08-01
- Expiration date of the lot/batch: 2020-07-30 (retest date)
- Purity test date: 2015-10-08

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature

OTHER SPECIFICS:
- purity: 98.9%
- appearance: white powder
- Water solubility: sparingly soluble

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Sampling method: samples for possible analysis were taken form all test concentrations and the control at t=0 and t=48h. 2.0 mL of volume was taken from the approximate centre of the test vessels. At the end of the exposure period, the replicates were pooled at each concentration before sampling
- Sample storage conditions before analysis: the samples were stored in a freezer. Additionally, reserve samples of 2.0 mL were taken for possible analysis

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation of test solutions started with the highest concentration of 100 mg/L applying 36-41 minutes of magnetic stirring to accelerate the dissolution of the test item in test medium. This resulted in a clear and colourless solution. The pH was adjusted from 5.7 (combined limit/range-finding test) and 5.3 (final test) to 6.5 with 1M NaOH (Merck, Darmstadt, Germany). The lower test concentrations were prepared by subsequent dilutions of the highest concentration in test medium.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): All final test solutions were clear and colourless.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water-flea
- Source: in-house laboratory culture with a known history
- Age at study initiation (mean and range, SD): <24h (from parental daphnids of more than 2 weeks old)
- Method of breeding: 250 newborn daphnids (i.e. less than 3 days old) are placed into 5 litres of medium in an all-glass culture vessel. Medium is M7. After 7 days of cultivation half of the medium is renewed twice a week.
- Feeding during test: no

ACCLIMATION
- Acclimation period: not relevant

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg/L as CaCO3

Test temperature:

20°C

pH:

At t= 0h: 6.5
At t= 48h: 7.7-7.8

Dissolved oxygen:

At t= 0h: 8.7-8.9
At t= 48h: 8.9-9.0

Salinity:

not relevant

Conductivity:

not relevant

Nominal and measured concentrations:

Final test
Nominal concentrations: 10, 18, 32, 56 and 100 mg/L
Analysed concentrations: 0, 100 mg/L
Measured concentrations at t=0h: n.d., 101 mg/L
Measured concentrations at t=48h: n.d., 101 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: beaker
- Material, size, headspace, fill volume: 100 mL, glass beaker filled with 80mL
- Aeration: not during the test
- Type of flow-through (e.g. peristaltic or proportional diluter): no flow-through
- Renewal rate of test solution (frequency/flow rate):no renewal, static system
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Photoperiod: 16h light daily

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobility was defined as those organisms which are not able to swim within 15 seconds after gentle agitation of the test container and was monitored after 24 and 48 hours of continuous treatment with the test substance.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Range finding study
- Test concentrations: 0.10, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

Potassium Dichromate

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% C.L.: not determined

Details on results:

- Mortality of control: none
- Other adverse effects control: no
- Abnormal responses: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50/LC50: 48h-EC50 = 0.58 mg/L. the sensitivity of the daphnia was within the range determined with the historical data collected at WIL Research Europe.

Reported statistics and error estimates:

No EC50-values could be calculated in the final test because the test item proved to be non-toxic (EC50 > maximum concentration tested).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of Isonicotinic acid to Daphnia magna was determined in a 48-hour static test according to the OECD guideline 202.
Under the conditions of the present study, the 48h-EC50 was behind the range tested, i.e. exceeding an analytically confirmed nominal concentration of 100 mg/L.
The results of the test can be considered reliable without restriction.